Road Salt Damage to Arborvitae
Last fall, we planted a staggered row of arborvitae along the road as a natural fence line about 4 to 6 feet from the road. The trees are 10 to 12 feet tall and seem to be doing well, except for the side facing the road. Sometime ago, you mentioned the salt on the roads during the winter posing a problem. The brown and yellow 'leaves' have been slowly dropping and the lower three to four feet along the roadside are becoming somewhat bare. I now know that they'll have to be protected against this in the future, but until then, is there anything I can do to bring back the greenery?
The best way to help your arborvitae is water thoroughly as needed and then wait.
If you haven’t mulched the soil, consider adding a 2 to 3 inch layer of woodchips or shredded bark over the soil surface around the plants. This helps conserve moisture and discourage weeds. Don’t pile it over the plant’s stems.
If the branches are pliable they may send out new growth. If the branch tissue is brittle it is dead and you might as well prune off the dead stems back to living tissue. The heavy shade produced by upper growth often slows or prevents new growth on the lower portions of the plant.
You may want to wait and see if the plant starts sending out new growth. Be patient it can take a year or more.
If space allows, consider planting salt tolerant low growing shrubs or perennials in front of the arborvitae to mask the bare stems and provide screening. Miss Kim lilac, rugosa rose, elderberry, Siberian pea shrub, barberry, forsythia and cotoneaster are a few of the salt tolerant shrubs.